There is known a camera system including an imaging apparatus and an interchangeable lens detachable from the imaging apparatus. In such an interchangeable lens type camera system, for example, there is an advantage that the interchangeable lens can be replaced in response to the photographing application, or the interchangeable lens can be replaced with a new product added with a new function.
In the interchangeable lens type camera system, when an interchangeable lens is mounted, a process of initializing each element (function) of the mounted interchangeable lens is necessary. For example, in a camera system of PTL 1, in a case where an interchangeable lens is mounted and power-on operation is performed, when a camera body transmits an initialization start command to the interchangeable lens, each driven member of the interchangeable lens executes an initialization process.